The King Devick Test for Concussion is a screening tool used to determine neurological functionality. The test measures planning and execution of saccades and rapid number naming to detect the presence of functional neurological deficits. It has proven to be an accurate method of measuring concussions in athletes and it is frequently used in this capacity.

Scoring

Participants are required to read a series of single digit numbers displayed on 3 test cards on an i-Pad device. The time required to complete each card is recorded in seconds and a cumulative score is established.

Comments

Sport-Related Concussion (SRC) Related: Population of interest: Adolescents and adults with SRC.

Advantages: The KD test has been shown to be responsive to the effects of SRC (medically confirmed or otherwise) and is easy to use and interpret. Many notable studies in the acute phase of concussion assessment have used assessment. Four clilnically-relevant studies in the subacute/chronic phase.

Limitations: It is not as easy as it used to be. The cards are no longer being sold. The program is available only as a licensed IPad-based product and thus not readily available to the full spectrum of potential users. It is well-validated for the diagnosis of concussion at the time of or within hours of injury but less so for the subacute (>72 hours) phase and for concussion recovery.

Timeframe best used: within minutes to hours of concussion. Therefore, it is most useful in the acute phase of concussion. It has been used in 4 other clinically-relevant studies from 1 day post concussion to > 30 days post concussion. In 2 of the 4 studies, K-D performance returned to baseline within 14–21 days of injury. In one study (Tjarks BJ et al. Journal of the Neurological Sciences 2013) K-D performance (without a baseline comparison), along with cognitive and visual memeory scores and symptoms on the ImPact test, tracked recovery over 30 (or more) days after injury, suggesting that the K-D test may also be useful to track concussion recovery.